A Windows zero-day vulnerability addressed this week by Microsoft with its November 2018 Patch Tuesday updates has been exploited by an advanced persistent threat (APT) group in attacks aimed at entities in the Middle East.
Microsoft learned about the vulnerability on October 17 from Kaspersky Labs. The security firm came across the flaw after one of its products detected an exploitation attempt against a Windows system. Further analysis revealed that it was a zero-day vulnerability related to the Win32k component in Windows.
The security hole, tracked as CVE-2018-8589, allows an attacker to elevate privileges on a compromised Windows 7 or Windows Server 2008 system. In the attacks observed by Kaspersky, threat actors had been executing the exploit through the first stage of a malware installer, but it’s unclear how the malware had been delivered.
According to Kaspersky, the vulnerability has only been used in a “very limited number of attacks,” with all the victims located in Middle Eastern countries.
The company could not say which threat group may be behind these attacks, but noted that the exploit is being used by “at least one APT actor.”
Kaspersky has released a blog post containing technical details on CVE-2018-8589, which it has described as a race condition.
This is not the only zero-day reported by Kaspersky to Microsoft in recent weeks. The company’s researchers have also been credited for discovering CVE-2018-8453, which Microsoft resolved with its October updates. The security hole had been exploited by the threat group known as FruityArmor in a highly targeted campaign.
Both vulnerabilities identified by Kaspersky were related to the Win32k component of Windows and they were both used in attacks aimed at users in the Middle East, but it’s unclear if there is any connection between the two.
“Autumn 2018 became quite a hot season for zero-day vulnerabilites,” said Anton Ivanov, security expert at Kaspersky Lab. “In just a month, we discovered two of these threats and detected two series of attacks in one region. The discreteness of cyberthreat actors’ activities reminds us that it is of critical importance for companies to have in their possesion all the necessary tools and solutions that would be intelligent enough to protect them from such sophisticated threats. Otherwise, they could face complex targeted attacks that will seemingly come out of nowhere.”